(1) Field Of The Invention
The present invention relates to radio frequency signal warning systems and more particularly, to a multi-function radar early warning system that provides an indication and warning of threats based on current and projected future radar systems.
(2) Description Of The Prior Art
Radar is commonly used to detect and locate objects or targets by radiating electromagnetic energy and using the echo or reflection of the electromagnetic energy from the object or target. In general, a typical radar system transmits one or more radio frequency signals to be reflected from objects in the environment. The radar system then receives and analyzes the reflected signals to determine the location or distance to the objects.
Different types of radar systems have used different types of radio frequency signals having a number of different frequency ranges or bands. For example, in a pulsed radar system, the transmitter transmits radio frequency signal pulses that are reflected from objects and then received to determine the distance to the object and the location of the object. In a continuous wave type radar system, a continuous radio frequency signal is transmitted. When the continuous wave is reflected from a moving object, the frequency of the wave changes, thereby providing an indication of moving objects in the environment.
Early warning radar (EWR) systems are commonly used by the military to detect and provide a warning of radar signals and possible threats posed by the vessels transmitting the radar signals. For example, underwater vessels, such as submarines, include periscope antennas that receive various types of radar signals on one or more channels.
Some problems encountered with existing EWR systems include the inability to detect a wide range of different types of radar signals. The existing EWR systems also do not provide an adequate indication of the type of radar signal that was detected.